Abstract: Image contributions produced by an untagged specimen magnetization component in magnetic resonance imaging are controlled by applying one or more radiofrequency (RF) pulses that invert at least a portion of the untagged specimen magnetization. In an example, a specimen is tagged with a spatially modulated magnetization that is used to produce an image signal that includes a contribution associated with the tagged magnetization and an untagged magnetization. The untagged magnetization is substantially along an axial direction defined by an applied axial magnetic field. The untagged magnetization increases in magnitude because of so-called T1 relaxation. A contribution to the image signal increases for a predetermined time or to a predetermined magnitude, and a 180-degree pulse is applied to invert at least a portion of the untagged magnetization. The untagged magnetization is then antiparallel with respect to the applied axial magnetic field.

Abstract: Magnetic resonance imaging method and apparatus are provided for mapping the internal or bulk motion of an object by labeling the phase of a specimen magnetization with a selected spatial function and measuring changes in the phase of the magnetization. The spatial function is selectable to provide magnetization phase modulation corresponding to displacements in a selected direction, such as a radial or azimuthal direction. Methods and apparatus for producing images based on magnetization phase modulation acquire image data based on stimulated echos and stimulated anti-echos. In an embodiment, a series of 180 degree pulses produces alternating stimulated and stimulated anti-echos that are measured and assigned to respective images.

Abstract: A method for obtaining an image by MRI, comprising: administering at least one contrast agent to a subject in amounts effective to perform CEDST MRI analysis; and performing CEDST MRI analysis to produce an image of the subject. A number of different contrast agents can be used to practice the present method including, without limitation, sugars, amino acids, nitrogen-containing heterocycles, purines and pyrimidines, nucleosides; imidazole and derivatives thereof, imino acids, barbituric acid and analogs thereof, and miscellaneous materials, such as guanidine hydantoin, parabanic acid, and biologically active salts thereof.

Abstract: Method for determining in vivo concentration of a metabolite that includes administering a contrast agent to a subject, allowing the contrast agent to disperse to tissue of interest, performing CEDST MRI analysis of the subject, and comparing the results to known in vitro results to determine metabolite concentration.

Abstract: Magnetic resonance imaging method and apparatus are provided for mapping the internal or bulk motion of an object by labeling the phase of a specimen magnetization with a selected spatial function and measuring changes in the phase of the magnetization. The spatial function is selectable to provide magnetization phase modulation corresponding to displacements in a selected direction, such as a radial or azimuthal direction. Methods and apparatus for producing images based on magnetization phase modulation acquire image data based on stimulated echos and stimulated anti-echos. In an embodiment, a series of 180 degree pulses produces alternating stimulated and stimulated anti-echos that are measured and assigned to respective images.

Abstract: A method for obtaining an image by MRI, comprising: administering at least one contrast agent to a subject in amounts effective to perform CEDST MRI analysis; and performing CEDST MRI analysis to produce an image of the subject. A number of different contast agents can be used to practice the present method including, without limitation, sugars, animo acids, nitrogen-containing heterocycles, purines and pyrimidines, nucleosides; imidazole and derivatives thereof, imino acids, barbituric acid and analogs thereof, and miscellaneous materials, such as guanidine hydantoin, parabanic acid, and biologically active salts thereof.